The present invention relates to a writing implement and particularly to a writing implement with self-contained illumination for selective illumination of the area surrounding the writing point.
Many writing implements with self-contained illumination have been proposed and constructed in the past. For example, in U.S. Pat. No. 1,298,384, there is disclosed a writing implement comprised of a pen barrel disposed in side-by-side relation with batteries in electrical contact with a bulb located at the writing end of the implement. Both the barrel, batteries and bulbs are disposed in a cylindrical housing. The lamp is illuminated by locating the cap on the end of the implement such that a band carried internally of the cap electrically connects a pair of contacts carried by the housing. Because the lamp is located to one side of the pen point, the illumination is such as to provide shadows in front of the pen point. Also, accurate location of the cap on the housing is necessary to electrically connect and maintain connection between the band and the contacts. Furthermore, the side-by-side relation of the pen barrel and batteries requires a housing which is of substantial thickness and consequently the writing implement is not particularly well adapted or facile for its intended purpose.
In U.S. Pat. No. 1,310,476, there is provided a writing implement having a lamp disposed behind an annular lens through which a writing implement is received. The body of the implement carries a battery and the lamp is energized by means of a switch which includes a slot and a shaped bar in the cap. While this illuminated writing implement is much thinner than the previously described implement, it does require manipulation of a switch to provide the illumination as well as fabrication of a number of switch parts which increases the cost of the implement.
U.S. Pat. No. 1,610,006 also discloses an illuminated writing implement which requires the cap to be screwed down upon the end of the barrel opposite from the writing tip in order to complete an electrical circuit to a lamp which projects laterally from a side of the barrel. Obviously, the lamp of this pen interferes with the use of the pen and likewise the illumination by the lamp casts undesirable shadows on the area adjacent the tip when writing. Other writing implements with self-contained illuminating devices such as described and illustrated in U.S. Pat. Nos. 1,509,719 and 1,987,158 have similar shortcomings and objections.